Island



(Mode1.)

J. M. WHITING.

SHEARS'.

No. 330,813. Patented Nov. 17, 1885.

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7 INVENTLTR! W ITN 555E15 WW.

side of a pair of shears.

the pivot-joint.

NrTED STAT S Price.

ATENT JAMES M. WHI'IING, OF PROVIDENCE, ASSIGNOR TO HIMSELF AND GEORGE W. PAINE, OF JOHNSON, RHODE ISLAND.

SHEARS.

SPECIFICATION forming part of Letters Patent No. 330,813, dated November 17, 1885.

Application filed April 22, 1885. Serial No. 163,071. (ModeL) Witha bearing-point, which, by moving forward from a lower position upon the inclined outer surface of the spring. will cause the grad ual depression of the said spring upon the closing movement of the blades, whereby an approximately uniform pressure may be secured at the crossing edge of the same from heel to point, as hereinafter fully set forth.

Figure l is an elevation of the right-hand Fig. 2 is a vertical view of the same with a portion broken away at the pivotjoint. Fig. 3 is a similar view showing the blades thrown open and with the handle of the left-hand blade broken away at Fig. 4 is a detail view illustrating the principle of my invention.

In the accompanying drawings, A repre.

sents the right-hand blade, and B the left-hand blade, into which is securely fixed the pivot pin 0, provided With a head, a, having an inclined annular inner surface, b, as shown in Figs. 2 and 3. At the outer side of the handle ofthe blade A is secured the'fiat outwardlyinclined spring D, the forward outwardly-inclined end, d, of which is made to embrace the pivotpin O, and to spring forcibly outward in contact with the bearing-point of the annular inclined face I) of the pivot-head, which bearing-point will be at the extreme lower edge of the said annular inclined surface. Whenever the blades A and B are fully opened for cutting, as shown in Fig. 3, the inclined surface I) should coincide in inclination with the outer inclined surface of the spring D, as shown in the said figure. The

head of the pivot-pin G will therefore at this point be somewhat relieved from the outward action of the spring D; but the spring should still provide sufficient pressure at the crossingpoint a of the blades to hold the same firmly together for cutting action upon any suitable material placed between them, and as the handles A and B are being brought gradually to- 5 gether in the operation of cutting, the action of the bearing-point of the inclined face I; upon the adjoining inclined side of the spring D will be such as to gradually increase the tension of the spring by forcing the same inward toward the adjacent side of the blade A until the blades have been brought in line with each other, as shown in Fig. 2, and by means of the increased tension of the spring, resulting from the closing movement of the blades, the proper degree of pressure at the cuttingpoint of the same will be secured from heel to point, the two blades being forced together at their cutting-edges by means of the resilient action of the spring D, operating from a rear fulcrum, e, at the contact-point of the inner side of the handles A and B.

In the above description I have set forth what I consider to be the preferable construction of the pivot-pin for securing the proper deflecting action upon'the spring during the closing movement of the blades, the head a serving to form a desirable finish for the device; but the practical result may be secured, as shown in Fig. 4, by the substitution of a laterally- 8o projecting pin or stud, f, for the inclined face b of the head a, the blades being in this case represented in the same position, as shown in Fig. 3, from which point the closing movement of the blades will cause the bearingpoint of the pin f to act against the outwardlyinclined surface of the spring, and thus deflect the spring inwardly toward the blade A, and cause an increased tension in the same as the handles A and B. are brought gradually o nearer each other in the operation of cutting, thus securing the desired uniformity of contact-pressure at the cutting-point of the shears from heel to point of the blades.

I claim as my invention The combination of the opposite shearblades, the pivot-pin secured to one of the blades, the inclined spring secured to the other blade, and a bearingpoint upon the pivotpin adapted to move upon the inclined surface of the spring, and thereby cause an increased tension of the same upon the closing movement of the blades, substantially as described.

JAMES M. WHITING. Witnesses:

SOORATES SOHOLFIELD, LEONARD SOHOLFIELD. 

